基于亮度特性的高空间分辨率遥感影像阴影处理研究

Processing Methods and Verification Examples of Shadows from High-resolution Satellite Images

在高密度的城市环境中,建筑物产生的阴影遮挡了许多重要信息,导致车辆信息提取不准确甚至无法提取,因此对阴影的处理显得尤为重要。利用遥感影像阴影的几何特征和光谱特征,采用基于亮度的阴影检测方法,通过双峰曲线选取合适的亮度阈值把阴影和光照区进行分割;并用灰度线性映射的阴影补偿方法,通过线性映射对阴影区域进行信息补偿,对高空间分辨率遥感影像的样本数据中的阴影进行试验处理和结果分析,结果证明这一方法是行之有效的。

In the high-density urban environment,building shadows can block a lot of important information,resulting in inaccuracies or even errors in image interpretation.According to the geometric and spectral characteristics of the shadow image,this paper uses a brightness-based method,which chooses bimodal curve to select the appropriate brightness threshold to split the shadow and light areas.Then,it uses a linear mapping grayscale shadow compensation method to compensate the information of the shadow region.At last,the sample shadow data from the high spatial resolution remote sensing image are used to verify the effectiveness of the method.The results show that this method is effective.